Is there evidence from motor tear down that synthetic oils keep your motor cleaner then conventional oils? Let's assume both motors were well taken care of one run on synthetic and one conventional after many miles.
Clean engine?
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I'd say it depends on the engine. I posted pics of my 2000 Century engine which my father owned since day one and took very good care of. It was serviced with brand name dino oil changes none exceeded 3K miles, at the dealer and local shops. It didn't look good after 80K miles. So I'd say it depends on the engine and the conditions in which it was used. I try and avoid blanket statements, they can get you in trouble.
In general yes, synthetic base stock oils just have inherently better cleanliness.
GF-5 dictates the same limits for deposits for both synthetic and conventional oils so I doubt there's much difference as long as the appropriate OCI are used. However, one must asked themselves do you think a synthetic oil is twice as good to justify the 2:1 price ratio? I don't and would rather have 2 changes of conventional at 7500 km to 1 change of synthetic at 15,000 km.
Synthetic oils are great in freezing temperatures where cold starts are common.
Freezer experiment: put 1-2 oz of reg oil in paper cup in freezer and do same with synthetic.
Take out after 1-2 hrs and tip the cups back and forth and see how thick reg oil is! The synthetic
oil seems nearly unaffected and flows easily.
That means a cold start won't mean slow /thick oil failing to lube main bearings and pistons as much as
reg oil.
Freezer experiment: put 1-2 oz of reg oil in paper cup in freezer and do same with synthetic.
Take out after 1-2 hrs and tip the cups back and forth and see how thick reg oil is! The synthetic
oil seems nearly unaffected and flows easily.
That means a cold start won't mean slow /thick oil failing to lube main bearings and pistons as much as
reg oil.
From the thread title and with the weather turning for the better, I thought this was about cleaning the engine bay.
Originally Posted By: SatinSilver
From the thread title and with the weather turning for the better, I thought this was about cleaning the engine bay.
LOL me too and I was curious since I just did that - but with a wet towel, brush and bucket of water for fear of soaking things too much - so was curious about this.
Regarding keeping the engine cleaner with conventional vs. synthetic, there is no real way of telling short of an engine tear-down right? I've never done an engine oil analysis but from what I understand that only indicates wear components and not any information on sludge buildup. I always try and peer down the oil fill area with my flashlight but not sure that really tells too much. I wish there were something like using a borescope down a spark plug hole to check for engine varnish.
From the thread title and with the weather turning for the better, I thought this was about cleaning the engine bay.
LOL me too and I was curious since I just did that - but with a wet towel, brush and bucket of water for fear of soaking things too much - so was curious about this.
Regarding keeping the engine cleaner with conventional vs. synthetic, there is no real way of telling short of an engine tear-down right? I've never done an engine oil analysis but from what I understand that only indicates wear components and not any information on sludge buildup. I always try and peer down the oil fill area with my flashlight but not sure that really tells too much. I wish there were something like using a borescope down a spark plug hole to check for engine varnish.
Depends on the engine, conditions, and OCI. Synthetic will require tougher conditions before it breaks down and leaves deposits, but it is possible to keep an engine (in most cases) clean with conventional - it just may be more wasteful than running longer on a syn.
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The definition is kind of blurred these days. A large proportion of any finished motor oil is additives anyways, and some of that includes deposit control. Higher performance oils do seem to sludge less in some applications, but then again the latest standards help regardless of how it's marketed.
Depends on the quality of the base stocks and the add pak. But, it also depends on the operating environment. Much of the "gunk" in engines is a form of condensate. Places like NY State with long'ish cold winters let the sheet metal parts of an engine (valve covers, oil pans, timing chain covers) cool off a lot and they want to condense evaporites. They also have little active oil flow over their surfaces - so they accumulate sludge. Prolly the best way to keep an engine clean is to get it hot and keep it there.
The second best way is to change oil to those with low NOAK and stout add paks.
And, I would be running a full can of say BG-109 (EPR) in the fall oil change if I lived anywhere like that.
Out here where a cold winter day is 40'ish, it's not as much an issue
The second best way is to change oil to those with low NOAK and stout add paks.
And, I would be running a full can of say BG-109 (EPR) in the fall oil change if I lived anywhere like that.
Out here where a cold winter day is 40'ish, it's not as much an issue
Conventional oils tend to varnish more (harmless) but after seeing an engine that had conventional oil cook off due to high temps it was nasty ! At least synthetic oil has a higher temp range and in the event your radiator goes it gives you a little extra cushion temp wise to pull over and shut down .
For any new vehicle today I would always run synthetic. The cost difference is not so much as it used to be. For most people the driving routine is the key for a better chance of a clean engine. If you drive highway speeds most of the time that gives you the advantage. My personal experience in the Sea-Tac metro where freeway speeds average 20 mph or so during commute hours with lots of stop and go is probably the same for many here living in large metros. That's harder on engine cleanliness. Short trips to grocery shopping or schools etc are the worst.
So having a better quality oil will give you the advantage over the old conventional oils. But In the end, driving climate and other factors weigh heavier on engine cleanliness than the oils themselves.
So having a better quality oil will give you the advantage over the old conventional oils. But In the end, driving climate and other factors weigh heavier on engine cleanliness than the oils themselves.
Originally Posted By: tig1
My 2007 Ford Fusion 2.3 at about 200K with 10K OCIs with M1 0-20AFE.
Looks great.
My 2007 Ford Fusion 2.3 at about 200K with 10K OCIs with M1 0-20AFE.
Looks great.
The base oil (synthetic or conventional) is not what keeps the internals cleaner, it is the detergent additive package in the motor oil. There are some conventional oils that have robust detergent packages that keep engines easily as clean or cleaner than many synthetic oils.
Now true, the cost difference is not that much, that using a synthetic all the time is cost effective. But even among synthetics, there is different add packs. And some will keep things cleaner than others. Many folks either don't know, or gloss over, that 20% of any motor oil is additive package. All synthetics offer over conventional is better extreme temperature protection, reduced shearing potential due to lower need of viscosity modifiers, and usually lower NOACK (burn off vaporization rate). And many synthetics will lighten folk's wallets a little quicker than conventional. But cleaning is solely the realm of the additive package in the motor oil.
The freeze thing is nice for discussion, but, for instance, a 5w30 conventional and a 5w30 synthetic have the same cold flow characteristics. Both meet a -30c / -23F CCS viscosity of less than 6000 cSt. Most of those freezer tests take the oil outside of their cold flow rating to dramatically prove a point. Just a little slight of hand thing going on playing on folk's ignorance.
Now true, the cost difference is not that much, that using a synthetic all the time is cost effective. But even among synthetics, there is different add packs. And some will keep things cleaner than others. Many folks either don't know, or gloss over, that 20% of any motor oil is additive package. All synthetics offer over conventional is better extreme temperature protection, reduced shearing potential due to lower need of viscosity modifiers, and usually lower NOACK (burn off vaporization rate). And many synthetics will lighten folk's wallets a little quicker than conventional. But cleaning is solely the realm of the additive package in the motor oil.
The freeze thing is nice for discussion, but, for instance, a 5w30 conventional and a 5w30 synthetic have the same cold flow characteristics. Both meet a -30c / -23F CCS viscosity of less than 6000 cSt. Most of those freezer tests take the oil outside of their cold flow rating to dramatically prove a point. Just a little slight of hand thing going on playing on folk's ignorance.
Originally Posted By: TiredTrucker
The base oil (synthetic or conventional) is not what keeps the internals cleaner, it is the detergent additive package in the motor oil. There are some conventional oils that have robust detergent packages that keep engines easily as clean or cleaner than many synthetic oils.
Now true, the cost difference is not that much, that using a synthetic all the time is cost effective. But even among synthetics, there is different add packs. And some will keep things cleaner than others. Many folks either don't know, or gloss over, that 20% of any motor oil is additive package. All synthetics offer over conventional is better extreme temperature protection, reduced shearing potential due to lower need of viscosity modifiers, and usually lower NOACK (burn off vaporization rate). And many synthetics will lighten folk's wallets a little quicker than conventional. But cleaning is solely the realm of the additive package in the motor oil.
But these days, what's the difference between a "conventional" and "synthetic"? Almost any "conventional" motor oil meeting the latest API specs is going to be mostly group II and might have some group III. It might even have some PAO or esters.
There's a pretty good argument to be made that these terms are a remnant of an earlier time when they might have actually meant something. A performance standard is probably more important than a marketing term on a label.
The base oil (synthetic or conventional) is not what keeps the internals cleaner, it is the detergent additive package in the motor oil. There are some conventional oils that have robust detergent packages that keep engines easily as clean or cleaner than many synthetic oils.
Now true, the cost difference is not that much, that using a synthetic all the time is cost effective. But even among synthetics, there is different add packs. And some will keep things cleaner than others. Many folks either don't know, or gloss over, that 20% of any motor oil is additive package. All synthetics offer over conventional is better extreme temperature protection, reduced shearing potential due to lower need of viscosity modifiers, and usually lower NOACK (burn off vaporization rate). And many synthetics will lighten folk's wallets a little quicker than conventional. But cleaning is solely the realm of the additive package in the motor oil.
But these days, what's the difference between a "conventional" and "synthetic"? Almost any "conventional" motor oil meeting the latest API specs is going to be mostly group II and might have some group III. It might even have some PAO or esters.
There's a pretty good argument to be made that these terms are a remnant of an earlier time when they might have actually meant something. A performance standard is probably more important than a marketing term on a label.
Who really cares what the difference is between conventional and synthetic, as it pertains to cleanliness of the engine internals of this thread? It is the detergent package in the oil that handles that, not the base oil. Even the best synthetic base oil, without a good additive package, will grenade an engine just as quickly. There is a lot more to motor oil than the base oil. Motor oil is a highly developed blend of many components. Detergents, Acid neutralizers, anti friction components, extreme pressure modifiers, oxidation control, viscosity modifiers, ethanol emulsion protection, etc. Even a top end synthetic base oil, by itself, can't mitigate all of what is going on in an engine. It needs help via the additive package. That is what makes a oil a API SN, ILSAC GF-5, API CJ-4, dexos1, or whatever spec it is made for.
Originally Posted By: TiredTrucker
Who really cares what the difference is between conventional and synthetic, as it pertains to cleanliness of the engine internals of this thread? It is the detergent package in the oil that handles that, not the base oil. Even the best synthetic base oil, without a good additive package, will grenade an engine just as quickly. There is a lot more to motor oil than the base oil. Motor oil is a highly developed blend of many components. Detergents, Acid neutralizers, anti friction components, extreme pressure modifiers, oxidation control, viscosity modifiers, ethanol emulsion protection, etc. Even a top end synthetic base oil, by itself, can't mitigate all of what is going on in an engine. It needs help via the additive package. That is what makes a oil a API SN, ILSAC GF-5, API CJ-4, dexos1, or whatever spec it is made for.
There was a time when "synthetic" generally means a PAO/ester blend, and the base oil was well known for resisting breakdown, and esters were very good at cleaning out deposits. It can't do it by itself, but it was a good starting point for clean internals. However, at this point I think a performance standard means more than what's essentially just a marketing term now. "Synthetic" kind of became more marketing-speak than anything else once Castrol started using group III and selling it as "synthetic" and when Valvoline started marketing all these different SynPower products as "synthetic" including fuel treatments and brake fluid, even though technically all brake fluid and fuel detergents are synthesized chemicals.
Of course there are always these odd outliers. Just look up Mobil's foray into aviation motor oils with Mobil AV-1. They ended up pulling it off the market because it had issues with leaded gasoline in certain engines.
Who really cares what the difference is between conventional and synthetic, as it pertains to cleanliness of the engine internals of this thread? It is the detergent package in the oil that handles that, not the base oil. Even the best synthetic base oil, without a good additive package, will grenade an engine just as quickly. There is a lot more to motor oil than the base oil. Motor oil is a highly developed blend of many components. Detergents, Acid neutralizers, anti friction components, extreme pressure modifiers, oxidation control, viscosity modifiers, ethanol emulsion protection, etc. Even a top end synthetic base oil, by itself, can't mitigate all of what is going on in an engine. It needs help via the additive package. That is what makes a oil a API SN, ILSAC GF-5, API CJ-4, dexos1, or whatever spec it is made for.
There was a time when "synthetic" generally means a PAO/ester blend, and the base oil was well known for resisting breakdown, and esters were very good at cleaning out deposits. It can't do it by itself, but it was a good starting point for clean internals. However, at this point I think a performance standard means more than what's essentially just a marketing term now. "Synthetic" kind of became more marketing-speak than anything else once Castrol started using group III and selling it as "synthetic" and when Valvoline started marketing all these different SynPower products as "synthetic" including fuel treatments and brake fluid, even though technically all brake fluid and fuel detergents are synthesized chemicals.
Of course there are always these odd outliers. Just look up Mobil's foray into aviation motor oils with Mobil AV-1. They ended up pulling it off the market because it had issues with leaded gasoline in certain engines.
I'd like to think synthetic cleans and works better overall which is why I use it! It's really not that much more money and can even be cheaper with rebates. Oil's the lifeblood of the engine, I see no reason to cheap out on it. Run good synthetic and good filters and it'll outlast the rest of the car.
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